Abnormal homocysteine levels can have various causes, ranging in severity from 'needs attention' to 'generally fatal'. Finding the true cause means ruling out or confirming each possibility – in other words, diagnosis.
Diagnosis is usually a complex process due to the sheer number of possible causes and related symptoms. In order to diagnose abnormal homocysteine levels, we could:
Cause | Probability | Status |
---|---|---|
Ulcerative Colitis | 90% | Confirm |
Chronic Renal Insufficiency | 14% | Unlikely |
Crohn's Disease | 5% | Ruled out |
Vitamin B-Complex Need | 5% | Ruled out |
Homocysteine (plasma). Unit: umol/L
Possible responses:
→ Don't know→ Under 5 → 5 to 9.9 (optimal) → 10 to 14.9 (elevated) → 15 or higher |
Homocysteine levels are often increased in patients with Crohn's disease. [Am J Gastroenterol. 2000 Dec;95(12): pp.3498-502]
Several studies have found that patients suffering from inflammatory bowel disease (IBD) such as ulcerative colitis and Crohn's disease are more likely to have elevated blood homocysteine levels (hyperhomocysteinemia).
Those suffering from IBD have a much higher risk of both thromboses and osteoporosis. Because elevated blood homocysteine levels are associated with an increased risk of atherosclerosis and thrombosis, a team of researchers from McGill University in Montreal explored the idea that homocysteine excess may play an important role in IBD.
To test this hypothesis, they measured homocysteine levels in the plasma of 65 patients with IBD and in 127 healthy controls. Their results revealed a striking difference: The patients with IBD had nearly a six-fold increased incidence of hyperhomocysteinemia (homocysteine levels above the normal range) compared to controls.
About one in every seven patients in the IBD group had hyperhomocysteinemia. As expected, those with vitamin B12 deficiency tended to have higher homocysteine levels. Yet researchers were also surprised to find that 80% of the IBD patients with hyperhomocysteinemia had normal blood levels of vitamins.
This suggests that homocysteine imbalances could be an early warning sign of B-vitamin deficiency inside cells – one that occurs well before vitamin levels actually decline in serum. It is still too early to tell if treating high homocysteine could actually reduce IBD symptoms in patients.
Importantly, as homocysteine levels rose in the patients with IBD, so did the clinical ratings of IBD disease severity, including its length of duration and the use of steroid medications to treat it. [Am J Gastroenterol. 2001 96(7): pp.2143-9]
Homocysteine imbalances could be an early sign of B-vitamin deficiency inside cells, one that occurs well before vitamin levels actually decline in serum. "Homocysteine may, in fact, be a more sensitive marker of vitamin B12, B6 or folate deficiency and... may precede deficiency of circulating vitamins." [Am J Gastroenterol. 2001 96(7): pp.2143-9]
Homocysteine levels in patients suffering from chronic renal failure are significantly elevated at an early stage. The kidney plays a very significant role in homocysteine metabolism but this does not occur during chronic renal failure. In addition, there is a decreased extra-renal catabolism, which contributes to the hyperhomocysteinemia state. [Hyperhomocysteinemia: A Role in The Accelerated Atherogenesis of Chronic Renal Failure?, Netherlands Journal of Medicine, 1995;46: pp.244-251]